Switch for motor driven grease machines



All-g. 30, 1932. K s, CLAPP 1,874,025

SWITCH FOR MOTOR DRIVEN GREASE MACHINES Filed Sept. l5, 1950 iw nl t', l.. f WM w .mfstructed in such msm 1s operable,

Patented Aug. 30, 1932 KENNETH S. CLAPP, OF OLEVELAND, OHIO SWITCH FOR MOTOR DRIVEN-GREASE MACHINES Application filed September 15, 1930.

This invention relates to 'devices for dispensing materials, and more particularly relates to a means for rendering the motorinactive to prevent the same from operating the -dispensing mechanism when the material level in a. reservoir falls below a certain level.

Grease pumps, particularly lubricators such as are used' in and about oil and vgasoline service stations, are at present cona manner that the mecharegardless of the quantity of grease contained in the reservoir of the device. The result is, that often it is supposed thatgrease is being pumped into `the transmission, differential or gear boxes of a vehicle or the like, when, as a matter of fact, the How of material has stopped, although the pump continues its operation, because the reservoir is empty. It is therefore one of the objects of this invention to provide ay means whereby the motor. actuating the pumping mechanism of a grease pump is rendered inactive when the material level in the storagereservoir recedes to a predetermined position.

Among other objects of the invention may be 4classed simplicity and economyT of construction of the device, together with dura.- bility and strength.

Still other objects of the invention and the invention itself, will become more apparent from the following description of some embodiments thereof, which description is illustrated by the and forms a part of the specification.

Briefly, the invention is particularly adaptable for lubricant dispensing.,r pumps which have a storage reservoir, in which the lubri-` cant is contained, and a follower plate adapted to rest upon the lubricant, which plate recedes toward the bottom of the reservoir with the lubricant as the lubricant falls. The follower plate is adapted to actuate a circuit breaker to open the circuit to the pump operating motor to render the motor inactive accompanying drawing,

Serial No. 481,937.

when the plate nears the bottom of the reservo1r, thus preventing operation of the mechanism when the reservoir is empty.

Referring to the drawing:

Fig. 1 is an elevation vlew of a pumping mechanismwith a circuit breaker mounted thereon;

Fig. 2 is an enlarged fragmentary sectional v1ew of a circuit breaker such as may be applid to the reservoir of the device of Fig. `1; an

Fig. 3 is a similar view of another type of circuit breaker which may be employed.

Referring more particularly to the figures(y of the drawing, throughout which like parts are designated by like reference characters, there is illustrated a lubricant dispensin mechanism mounted upon a mobile truclgr which comprises a platform 10, supported upon legs 11 with suitable castors 12 for rendering the same mobile. f

The device may include a storage reservoir v 13 having a follower plate 50, disposed there' in and adapted to rest on the top of the lubricant. A screw vconveyor or pump is disposed in the housing 14 at the bottom of the reservoir, which conveyor is adapted to be operated by a motor 15,.

A screw conveyor and the parts ancillary to a pumping mechanism such as might be used are more fully described in the application of Kenneth S. Clapp, for lubricator, Serial No. 301,053 filed August 21, 1928.

A cable 17, which is adapted to be connected to a local source of electric power supply, not shown. is connected to the device.l One wire from the cable connects directly to the terminal 17 on the motor. The other wire is connected to one wire of an electric cable 18, which contains two wires. The other wire in the cable 18 is connected directly to the motor. The two wires in the cable extend, as shown in Fig. 1, alongA the dispensing conduit 22 to a control switch 20 which is disposed on the end of the dispensing l cable 18 may be interrupted by a circuit breaker 21 disposed adjacent the bottom of the reservoir 13. The circuit breaker 21 is normally in a closed position and the switch 20 is normally in an open position'. It is also obvious that the circuit breaker 21 might be connected into the power line 17 ahead of the motor 15.

When the nozzle 19 upon the end of the` dispensing hose 22 is secured to a greasing coupling or is inserted into an aperture such as a filler hole in a gear box or the' like, the switch 20 on being closed completes the circuit from the power line to the motor setting the same into operation. The motor 15 continues to operate, with the electrical current controlled by the switch 2() at the will of the operator, until the level of the material falls to a predetermining point, whereupon the circuit is interrupted by the action of the circuit breaker 21.`

The circuit breaker 21 is disposed on the side wall 30 of the. storage reservoir 13 and in the plane of a predetermined minimum surface level of the material within the reservoir. The side wall of the reservoir is apertured at 31j, land the operating lever arm 44 of the circuit breaker 21 may extend therethrough.

vThe circuit breaker 21 may include a base plate 32 adapted to be secured to the side wall 30 of the reservoir, a cylindrical or cup shaped metal housing 38, which may be constructed by stamping or other suitable means is secured to the base plate 32 and reservoir wall 30 by bolts 51. A pair of Contact arms 36 and 40 are secured to the circuit breaker housing 38, by means of bolts 39 and 42, bein vsuitably insulated from the housing wall an each other by insulating strips 52. The bolts which securev the arms to the housing wall extend therethrough and serve as 'terminal binding posts for connecting the switch into the circuit. A pair of contact points 37 andV 41 are carried by the arms 36 and 40.y

' The contact arm 36 may be of resilient metal and has a portion .35 extending beyond the end of the arm v40 which extension is suitably insulated by an insulating strip 54. An

.operating arm '34 is adapted to press against the insulating portion 54. The arm 34 is an extension of a cylindrical or a spherical segment bearing 53 with its convex surface seated in a like curved portion 33 of the base plate 32.

The curved portion 33 of the base plate is slotted or apertured at 43 and an operating pin 44, which is rigidly aixed to the bearing 53, extends through the slotinto the reservoir 13.- The pin 44 is disposed in the downward path of the `follower plate 50. A boss or pin 45` projects from the inner surface of the bearing portion 53 of the breaker arm and one end of a relatively still helical spring 46 is disposed aboutthe pin and the y other end of the spring is disposed around a pin 47 adjustably supported by the housing 38. The. pin 47 is an extension of an adjusting screw 48 which is threaded into an aperture in the housing 38 in alignment with the boss 45 and is locked in an adjusted position, for any tension desirable upon the spring, by a lock nut 49. The spring 46 provides a means to firmly maintain the bear-p ing portion of the breaker arm 34 in contact with the seat portion 33 of the base plate 32 and also permits pivotal movement of the breaker arm 34 and the operat'ingpin 44, and returns the breaker arm to a normal posi- .tion as illustrated.

Operation of the device is asfollows:

As previously stated, the storage reservoir 13 is filled with a supply of lubricating material or the like which it is desired to dispense. In dispensing the same the nozzle 19 on the end of the hose 18 may be inserted into a lillerhole or the like of a gear box. The desired amount of lubricant is pumped into the gear box by closing the switch 20. `Closing the switch 20 completes the circuit to the motor 15 causing the motor to operate the pumping mechanism. Opening of the circuit by the switch 20 causes thev motor and pump to cease operating.

As the material in the reservoir is removed by the action` of the pump the surface level of the remaining material recedes allowing the follower plate 50 to drop. When the level of the lubricantrecedes to a point adjacent the circuit breaker, the edge of the follower plate 50 will strike the projecting arm 44 of the circuit breaker 21, as shown in Figure 2, and on further recession of the level of the `lubricant the follower plate will pivot the breaker arm in its curved seat and this will cause the projecting end thereof to raise the end of contact arm 36 `thus separating the contact points 37 and 41 and'interrupting the flow of current in the circuit. It will then be impossible to complete the circuit by closingthe switch 20 and the operator will then know that the supply of lubricant in the reservoir has become exhausted. He may then withdraw the .follower plate and refill the reservoir. On withdrawal of the follower plate the spring 46 will permit pivoting the breaker arm back to its normal position withdrawing the arm 34 from contact with the sol silient contact arm to the arm 36 1n the modifica ion shown in,

bottom of the reservoir together with the housing 61 by means of bolts 62.

The circuitbreaker may comprise a plate 63 provided with a centrally bored exernally screw threaded boss 64 whlch functions as a 67 is disposed through the boss and has an'enlar ed head .68 the shoulder of which is normal y maintained against the end face of the packing nut byvmeans of the helical spring 69 which encircles Lthe inner end of the plunger 67 and is interposed be? tween theinner face of the plate 63 and a A plunger washer 7 0 which is held on the plunger 567 by means of a laterally projecting pin.71. The

outer end of the head 68 is normally disposed against the insulated extended end 72 of re- 7 3 which arm is similar Figure 2. (lo-operating with rm 73 is another contact arm 74 and these contact arms are secured to the circuit breaker-housing 61 in a manner similar to that in which arms 36 U the reservoir the plunger .bottom thereof, the

and are secured to housing 38. The circuit breaker is connected into the circuit in the same manner as the, other embodiment previously described. u

When the level of the lubricant in the reservoir 13 recedes to a point closely adjacent the follower plate ,50 will bear down on the plunger 67 which will in turn break the contact between the contact arms 36 and 40 and thereby opening the cirlubrithe follower plate to relill will be restored to cant. On lifting of yits normal position as shown 1n Figure 2 thus bringing the contact points together and making it possible to again operate the motor 1 5 to deliver lubricant from the reservoir.

Although the^ foregoing description is necessarily detailed to fully set forth the precise operation of thedevice it is to be understood that variations and modifications may be resorted to without departing from 4the spirit of the invention as definedby the following' claims.

I claim: v 1. In a pressure lubricating device, a lubricant reservoir, a follower plate in said reservoir, a motor driven pump for delivering lubricant from said reservoir, a circuit break-.n er in the power line leading to said motor adapted to be actuated by the follower plate when the levelgof the lubricant inthe reservoir and hence the follower plate recedes to a predetermined level and means for restoring said circuit breaker to normal position to permit fiow of current therethrough when the level of the lubricant is raised above said predetermined level. i 2f. In a dispensing device, a reservoir, a follower plate in said reservoir adapted to follow the liquid le'vel in the same, a motor driven pump for delivering liquid in the A and mounted within `pump, said mechanism comprising ydriven pump reservoir from the same, a circuit breaking mechanismin the power pump, said mechanism comprising a housing mounted on 4said reservoir on the side thereof, a pair of'contact elements in said power line said housing adapted uponopening to open the circuit leading to said pump, an varm mounted for pivotal movement on the side of the reservoir and projecting intosaid reservoir into the path of said foliower plate, a lever secured to said arm and adaptedl upon pivotal movement of said arm to engage one of said contacts and cause opening of said pair of contacts, and means preventing liquid in said reservoir from enteringsaid housing whereby said contacs are maintained free from foreign materia 3. In a dispensi g device, a reservoir, a follower plate in said reservoir adapted to follow the liquid level' in the same, a motor driven pump yfor delivering liquid in the reservoir from Athe same, a circuit breaking mechanism in the power line leading to the a housing mounted on said reservoir on the side there'- of, a pair of contact elements in 'said power line and mounted within lsaid housing ladapted upon opening to open the circuit leading to said pum there being an opening in the side of sai reservoir adjacent the bottom thereof communicating the interior of said reservoir with said housing, comprising a seat, a closure member for said vseat having limited pivotall movement with respect thereto, an arm onsaid closure member projecting into the path of said follower plate, a pair of contacts in the powerl line leading 'to said pump adapted upon "opening to break the power line circuit, and a lever secured to said closure member and adapted to engage one of said contacts to open the pair of contacts.

4. In a dispensing device,l follower plate in `said reservoiradapted lto follow the liquid level in the same, a motor for delivering liquid in the reservoir from the same, a circuit breaking mechanism inthe power line leading to the pump, said mechanism comprising a housing mounted on said reservoir'on the side thereof, a pair of contact elements in said power line and mounted within said housing adapted upon opening to open the circuit leading to said pump, there being an opening in the seat of said reservoir adjacent to the bottom thereof communicating the interior of a reservoir, a

line leading to the said opening..l

said reservoir wlth said housing, said opened upon opening to break the powerline circuit, an arm on said closure member projecting int/o the path of said follower plate, and

a lever secured to said closure member and adapted to engage one of said contacts to open the pair of contacta In testimony whereof I hereunto aiix my signature this 13 day of Se tember, 1930.

KEN NET S. CLAPP. 

